Variable stiffness heating catheter

Abstract

The variable stiffness heating catheter includes a heating catheter shaft including at least one electrically conductive member, a reinforcing tube with apertures formed around the surface of the reinforcing tube, and at least one coaxial outer layer of a polymer, metal, or both for providing desired variations in stiffness along at least a portion of the length of the shaft. The apertures can be formed as axial or helical slits in the surface of the reinforcing tube, and the reinforcing tube can also be formed to be tapered at the point where the apertures are formed in the reinforcing tube to provide a heating catheter that is torqueable and pushable at the proximal end, yet soft and flexible at the distal end.

Description

RELATED APPLICATIONS[0001]This is a continuation-in-part of Ser. No. 09 / 275,485 filed Mar. 24, 1999, now U.S. Pat. No. 6,352,531.BACKGROUND OF THE INVENTION[0002]1. Field of the Invention[0003]This invention relates generally to interventional medical devices, and more particularly concerns a heating catheter having variable stiffness for enhanced performance of the catheter shaft when used with or without a guide catheter, as a part of a therapeutic system or for delivery of medical devices.[0004]2. Description of Related Art[0005]Conventional minimally invasive catheter based therapies typically require guide wires that are one to two meters long extending through a longitudinal lumen in the catheter, and that are torqueable and pushable at the proximal end, yet soft and flexible at the distal end. Many such guidewires are made of stainless steel or the like, and are ground to tapers which provide the desired bending properties along the guidewire. Recently, numerous minimally inv...

AI Technical Summary

Benefits of technology

"The present invention provides a variable stiffness heating catheter shaft that can be more pushable at the proximal end and more trackable at the distal end, with a wide range of predictable variations in stiffness and other structural parameters over the length of the shaft. The heating catheter can be coated or heat shrunk with a reinforcing tube and an outer layer of a polymer, metal, or both, to provide desired variations in stiffness and softness at the different ends. The heating catheter can be used in vascular interventional therapy, such as in a tortuous, small diameter vessel, and can be made from a minimum number of components. The invention allows for a more flexible and maneuverable device at the distal end while maintaining a stiff and manageable device at the proximal end."

Problems solved by technology

Typically, such a heating catheter shaft can be formed from one or more electrically conductive members or the like which alone have physical characteristics that are undesirable for guidewires or pusher devices.

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